Friday 4 August 2006 19.04 EDT
First published on Friday 4 August 2006 19.04 EDT

At the moment of his untimely death a year ago this weekend, Robin Cook was preoccupied with the twin challenges of rising popular disengagement from politics and the need for Labour to rebuild its crumbling electoral coalition. Labour had recently secured a third consecutive term with the lowest winning share of the vote in history and the support of barely one in five registered voters. It had lost the support of 4 million voters since 1997. Cook was greatly concerned by the implications of this legitimacy deficit, yet was confident of his party's ability to respond by drawing on its strengths and embracing change.

I wonder if that optimism would have survived another year in which Labour's position has continued to erode at an alarming rate. Knowing him as I did, having worked with him for 11 years, I believe that it would. But there would also have been mounting exasperation at the reluctance of colleagues to face up to the urgency and scale of the task. He had anticipated Labour's disastrous performance in this year's local elections as the price of refusing to change, but would have been surprised and disappointed at the passivity of its reaction. He would have seen in this refusal to take the electorate seriously a tendency - increasingly common in New Labour - to mimic some of the worst traits of old Labour.

Cook would certainly have had plenty to say about the issues that have dominated the headlines since his death, and are likely to determine the shape of the post-Blair era. Indeed, there aren't many debates in which he wouldn't have figured as an influential voice. This is particularly true when you consider that so many of the government's present difficulties could easily have been avoided if only Cook's advice had been taken more seriously when he was alive.

Take loans for peerages, the latest crisis to contribute to the collapse in political trust that so worried him. Whether or not the police uncover any corruption, the appearance of impropriety is real enough and will do lasting damage to Labour's reputation. How different it would be if Cook's warning about the trust-corroding effect of choosing patronage over democracy had been heeded in the debate on Lords reform.

Tony Blair would surely be in a better position today if he had supported Cook's proposal for an elected second chamber rather than sabotaging it. There would have been no peerages for parties to hand out, and therefore no suspicion that they were being traded in exchange for secret donations. Schadenfreude was not Cook's style, but he would have been entitled to feel vindicated. If there is one lasting consequence of this scandal, it should be that the power to decide who sits in the upper house is put where it belongs in any self-respecting democracy - in the hands of the people.

Nowhere has Cook's wisdom and moral leadership been more sorely missed than in the Middle East and George Bush's ill-conceived war on terror. Recall his widely admired resignation speech in which he spoke of "the strong sense of injustice throughout the Muslim world at what it sees as one rule for the allies of the US and another rule for the rest". That sense of injustice now burns deeper than ever thanks to an American president who seems to delight in parading his double standards. It is inflamed when our prime minister joins him in pontificating about the evils of Islamist terrorism while remaining mute about the cruelties inflicted on the populations of Lebanon and Gaza by the Israeli government.

Cook would have been baffled at Blair's inability to learn from his own mistakes in tying himself so closely to a discredited White House, and despairing at the further heavy cost to Britain's international standing that has resulted. But he would not have been entirely surprised. One particularly malign effect of Blair's Iraq decision has been to destroy the European option in British diplomacy by dividing the continent and disabling it politically. Restoring that option after the failure of the European constitution was a project Cook considered particularly important at the time of his death. Again, he saw it as a problem of political disengagement, that needed to be addressed with a renewed sense of purpose, this time at a European level.

Cook would have regarded the government's response to the Lebanon crisis as more than just a policy error. He would have seen it as symptomatic of a deeper moral failing on Labour's part: an apparent reluctance, against its own history, to stand up for those who need it most. Instead of working for a fairer distribution of wealth and power, the government often seems more concerned with the interests of those who have too much of both. It was entirely fitting, for example, that in the week Blair travelled to America to parrot Bush's unconditional support for Israel, he took a detour to kiss Rupert Murdoch's ring. How little things have changed.

The hope that Cook embodied was for nothing less than the remoralisation of Labour. This could be taken in both senses, for he knew that Labour could not restore its morale in time to win another election unless it recovered its self-belief as a party of progressive social change. It is possible that he may have returned to the cabinet to contribute to that effort, although the personal happiness he discovered at the end of his life made him reluctant to consider it.

Either way, he was certain to have been a major influence on the next stage of Labour's political development. One particularly vital contribution would have been to counterbalance the efforts being made to cajole Gordon Brown into adopting a narrow Blairite agenda - efforts that appear to be having rather too much success. Ironically, given accepted wisdom about their relationship over the years, Cook would have been the first to urge Brown to have more confidence in his ability to succeed on his own considerable merits.

Whatever else passed between them, Cook had tremendous regard for Brown's commitment to social justice and his abilities as a politician. It would have pained him to think that Brown might diminish his potential to be a great prime minister by adopting the mantle of a lesser man. When Cook talked about renewal, he meant something much more than just a change of face at the top. He meant the willingness to embrace a different kind of politics. It is a vision that must survive him if Labour is to win again.

· David Clark was an adviser to Robin Cook from 1994 to 2001 Dkclark@aol.com